For the filling, beat the butter with sugar, mix the yolks with the lemon zest. Gradually grind both mixtures with cottage cheese and sour cream. Add raisins. Whisk egg whites with vanilla sugar and fold into curd mixture. Grease a baking dish with oil. Spread the curd filling over the pancakes, roll the pancakes into a tube, cut in half diagonally. Put the pancakes into the mold. Lightly beat egg yolk with sugar and milk. Pour pancakes with this mixture. Bake in a preheated oven at 180ºC for 20-25 minutes, then sprinkle with powdered sugar.